a 0.4 kg block rests on a desk. the coefficient of static friction is 0.2. You push the side of the block but do not have a spring scale to measure the force you use. the block does not move. which statement is true about the force of static friction?
Answers
Answer:
D. It is no smaller than
Explanation:
The question is incomplete. These are all the options :
A. It is no larger than
B. It is
C. It is
D. It is no smaller than
To solve this problem, we have the data of :
Where ''m'' is the mass of the block
μ = 0.2
Where ''μ'' is the coefficient of static friction
If we want to find the magnitude of the force of static friction we need to use the following equation :
μ.
(I)
Where '''' is the normal force that the desk exerts on the block. Its magnitude is equal to the weight (because we suppose that the block rests horizontally on the desk).
The weight '''' can be calculated as :
Where ''m'' is the mass and ''g'' is the acceleration due to gravity.
The value of ''g'' is
The weight of the block is
Now, the weight is equal to the normal force ⇒
Using the equation (I) :
The correct option is D. It is no smaller than
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This is collection of quantitative data made by comparing a quantity with a standard unit. In science, the units are metric.
Air is forced through the water to remove gases is called?
A horizontal line on a distance-time graph means the object isa. moving at a constant speed. b. moving faster. c. slowing down. d. at rest.
Answers
Answer:
15.7m/s
Explanation:
To solve this problem, we use the right motion equation.
Here, we have been given the height through which the ball drops;
Height of drop = 14.5m - 1.9m = 12.6m
The right motion equation is;
V² = U² + 2gh
V is the final velocity
U is the initial velocity = 0
g is the acceleration due to gravity = 9.8m/s²
h is the height
Now insert the parameters and solve;
V² = 0² + 2 x 9.8 x 12.6
V² = 246.96
V = √246.96 = 15.7m/s
Answers
Answer : Yes, distance measurements based on the speed of light used for objects in space.
Explanation : A light year is measurement of distance that light travel in a one year.
In a one year light travels 9460000000000 kilometer.
We know that, speed of light is
and time is 31536000 seconds in 1 year
so, distance= speed of light X time
Now, the light year is
Example : The nearest star to earth is about 4.3 light year away.
Answers
The velocity of the stone when it is 5.25 m above the ground is determined as 6.93 m/s.
Velocity of the stone
The velocity of the stone at the given displacement is calculated as follows;
K.E = ΔP.E
¹/₂mv² = mgh
v = √2gΔh
v = √[2(9.8)(7.7 - 5.25)]
v = 6.93 m/s
Thus, the velocity of the stone when it is 5.25 m above the ground is determined as 6.93 m/s.
Learn more about velocity here: brainly.com/question/4931057
#SPJ1
Answers
Answer:
a. 80 J/cell b. 1.02 × 10²¹ W/m² c. 8.77 × 10¹¹ V/m d. 2.92 × 10³ T
Explanation:
a. We know that energy E = Pt where P = power and t = time
The total energy delivered to all the 100 cells is E = average power × time
average power = 2 × 10¹² W and time = 4 ns = 4 × 10⁻⁹ s
E = 2 × 10¹² W × 4 × 10⁻⁹ s = 8 × 10³ J
The energy per cell E₁ = E/100 = 8 × 10³ J/100 = 80 J/cell
b. Intensity, I = P/A where P = power per cell = 2 × 10¹² W/100 = 2 × 10¹⁰ W and A = area = πr². Since the cell is modeled as a disk of diameter d = 5.0μm, r = d/2 = 5.0 μm/2 = 2.5 μm = 2.5 × 10⁻⁶ m
I = P/A = P/πr² = 2 × 10¹⁰ W/π(2.5 × 10⁻⁶ m)² = 1.02 × 10²¹ W/m²
c. The intensity I = E²/2cμ₀ where E = maximum value of electric field, c = speed of light = 3 × 10⁸ m/s and μ₀ = 4π × 10⁻⁷ H/m
E = √(I2cμ₀) = √(2 × 1.02 × 10²¹ W/m² × 3 × 10⁸ m/s × 4π × 10⁻⁷ H/m) = 8.77 × 10¹¹ V/m
The maximum magnetic field B is gotten from E/B = c
B = E/c = 8.77 × 10¹¹ V/m/3 × 10⁸ m/s = 2.92 × 10³ T
Answers
So, Ruff's image will be 3 m behind the mirror and 50 cm tall.
b. Ivan Pavlov
c. Elizabeth Loftus
d. John Watson
Knowing the formula for water and table salt is an example of:_________________memory.
a. episodic
b. procedural
c. semantic
d. echoic
The part of the brain that appears to be involved in the processing of short-term memories into long term is the:
a. hypothalamus
b. hippocampus
c. corpus callosum
d. cerebrum
Answers
1. Mary Cover-Jones
2.Knowing the formula for water and table salt is an example of episodic memory. so d
3.Hippocampus
Answer:
1) Mary Cover-Jones
2) episodic
3) hippocampus
Hope this helped man!